Jack construction



' March 26, 1940.

J. H. NEEDHAM JACK CONSTRUCTION Filed Dec. 21, 1958 film/es fi 4228554 .4 4m M m m mg K PatentedMar. 2c, 1940 2,195,094

IUINITED' STATES, PATENT OFFICE James HQNcedliam, Detroit, ich, assignor to Walker Manufacturing Company, Racine, Wis., a corporation of Wisconsin Application December 21, 1938, Serial No. 247,084

' 5 Claims. (01. 254-106) The invention relates generally to jacks and it Fig. 5 is a detail view illustrating a pair of has particular relation to a jack adapted for use clutch elements constructed according to one in'conjunction with motor vehicles. form of the invention.

In certain respects the invention constitutes Referring to Fig. 1, a motor vehicle is indicated it an improvement over that disclosed and claimed at H! and it is to be understood, due to the con- 5 in the application for patent now pending of struction of the vehicle, that it is more desirable 1 Earl G. Gunn, Serial No. 191,050, filed February to raise any one wheel when necessary by en- 17, 1938. In that application for patent, a jack gaging the jack with a projecting part of the is provided which embodies a pair of relatively vehicle, such as the bumper indicated at II.

it}; movable members, one in the form of an .elon- Raising the one wheel in this manner necessarily o gated bar, and a. friction clutch device for efrequires considerable movement of the bumper i"ecting movement of the one member relative as the spring allows the wheel to remain on the to the bar. This device includes a pair of plates ground during initial raising of the bumper. As slidable one on the other which have openings shown by this figure, the jack engages the bump through which the barextends and by cantlng er II and includes an elongated bar I! which has the plates, their edges around the opening bind a base l3 adapted to rest on the ground. aga st the bar and become anchored ther on, Now referring to Figs. 2, 3, and 4, this bar is Two pairs of these plates are employed, one pair slidable vertically through a housing l5 which serving as a'support for repeatedly raising the comprises two parts 16 and I! that are joined 53 one member and the other serving as a means together at their meeting edges by folded-over 2o for locking said member in its elevated p ositions. edge portions indicated at i8. At its lower and One object of the present invention is to proupp ds the us is formed t pr v w'de in a jack of generally the above specified cylindrical bearings 20 and 2| that closely but type an improved means for obtaining a frictionslidably receive the bar l2. The latter bearing 9% a1 connection between the plates and the bar so por 2| extends through a e e t 22 avi g as to render the jack more eflicient and positive a hook portion 23 adapted'to engage the bumper in operation and more durable in use. and such element rests on a shoulder 25 at the Another object of the invention is to provide lower end of the bearing and is retained thereon improved frictional means for connecting the by an outwardly directed flare 25 at the upper plates to the elongated bar wherein. the surface end of the bearing. 80 engagement between the bar and plates is operr levating the housing w respect to the atively increased to a. substantial extent with ut bar i2, plates and 3! are provided which have the use of additional plates. openings slightly larger than thebar and the Another Object of the invention'is to provide latter extends through these openings. Within J 55 an improved jack of the general character indithe p s, aw elements 32 and 33 e p o- 35 cated, wherein the improvements are obtained vided and e o these has flanges 35 at s pp in an inexpensivemanner. and lower ends for normally retaining it against Other objects of the invention will become ap- Y axial removal from the openings. Such jaw eleparent from the following specification, fro 'th ments are also shown in detail in Fig. 5 and .each drawing to which it relates, and from. the claims is slightly less than semi-cylindrical so that when 40 hereinafter set forth. the jaw elements fit against the bar l2, a gap 35 F01 a better understanding of the invention, exists between the edges of the elements. The reference may be had to the accompanying gap is desirable so as to insure contact of the drawing, in which: I elements with the bar before any contact of the Figure 1 is a fragmentary view illustrating a edges of the elements can occur, and to.prevent motor vehicle and a jackin operative relation turning inihe Openings as pr y Will be thereto wherein the latter is constructed accordserved. It will be noted also that each of the ing to one form 01' the invention; jaw elements axially of the openings is slightly I Fig. 2 is a'fragmentary view illustrating a longer than the combined thickness of the plates vertical section of the jack shown by Fig. 1; 30 and 3| and this is necessary so as to permit 50 Fig. 3 is a cross-sectional view on a. larger canting of the plates relative to the bar. scale, taken substantially: along the .line 3-3 As shown by Figs. 3 and 4, the sections I6 and f F ll of the housing at one side of and interme- Fig. 4 is a cross-sectional view on alarger scale di'ate the upper and lower ends of' the latter, intaken substantiallyalong theline H of Fig. 5': stead of being joined byIfolded-overfedge portions, have flanges and 4| defining an open slot 42. The plates 30 and 3| have tongues 43 projecting loosely into this slot. For canting the plates a socket member 44 is employed which is pivoted on a pin 45 extending across the slot and secured at its ends to the flanges and this member has a pin 46 that rests on and is adapted to fulcrum on the upper tongue. A handle 4! flts the socket member and serves to increase the leverage obtainable. p

A coil spring 50 around the bar l2 at the under side of the lower plate 3| presses at its lower end against the upper end of the bearing 20 and at its upper end against a ring 5| that has an axially offset rim 52 secured to the plate by pins 53. The spring naturally' urges the ring 5| upwardly and tends to support it and the plates 30 and 3| in positions normal to the bar I2 and hence any tendency to cant or cock the plates 30 and 3| by operating the hand lever 41 is resisted by the spring. It may be mentioned that the ring 5| has inwardly projecting tongues 51 on opposite sideswhich project into the gap 36 between the jaw elements 32 and 33, and this arrangement prevents rotational movement of the jaw elements in the openings in the plates.

From the foregoing, it will be apparent that, upon raising the handle 41, the pin 46 at the inner end of the socket member 44 cantsthe two plates 30 and 3| and thus forces the two jaw elements 32 and 33 against opposite sides of the bar l2 and this anchors the plates on the latter. Further movement of the handle 41 upwardly necessarily raises the housing relative to the bar l2 since the pin 46 fulcrums on the upper plate 7 30 and the housing is raised by the handle acting through the pin 45.

Directing attention now to Figs. 2 and 3', a pair of similar plates and 6| are provided above plates 30 and 3|, which have portions 63 projecting into a recess 64 in the housing and this recess, as shown by Fig. 2, has a shoulder 65 at its upper side that engages the upper side of the a portion 63 of the upper plate. Diametrically opposite to the portions 63, the plates 66 and 6| have tongues 64 which project through the slot 42. A coil spring 65, disposed on bar l2 and seated in a spring retainer 66 at its lower end, serves to urge the plates 60 and 6 upwardly and, since the-plate 66 engages the shoulder 65, the spring tends to cant the plates. As shown by Fig. 4, the spring retainer 66 has diametrically opposite projections 69 and 10 which project into apertures II and 12 formed in opposite sides of the housing and thus the spring retainer is anchored against axial or rotary movement. .The position of this spring retainer is so related to the plates 30 and 3| below it that it serves as an upper limiting and positioning member for such plates and the jaw elements associated therewith, as well as a positioning member for the lower end of the spring-65.

ing in the openings in the plates. The spring 65 abuts the two projections 16 and I1 and through this abutting engagement tends to push the plates 60 and 6| upwardly.. It will be noted in Fig. 2 that a lug 19 is provided on the housing for engagement with one edge of the tongue 64 for'engagement with the opposite edge of the tongue 64. These lugs limit downward movement of the plates 60 and 6| at that side of the housing opposite the portion engaging the shoulder 35.

In operating the jack, when the handle 46 is raised, the plates 30 and 3| are canted, thereby locking them to the bar l2 through engagement of the jaws 32 and 33 with the bar and then continued movement of the handle upwardly raises the housing. As the housing begins to raise, the shoulder 65 tends to leave the upper plate 60, and thus these plates are allowed to move towards positions normal to bar l2, thereby freeing the jaws 32 and 33 in such plates from bind-, ing engagement'with the bar. Since the housing carries the lower spring retainer 66, and, therefore, the spring 65, the plates 60 and 6| follow the shoulder 35 in its upward movement and as soon as the handle 41 is released and the weight presses the housing downwardly, the plates 60 and 6| are again canted sufliciently by engage- -ment of the shoulder 65 therewith, so as to bind the upper jaws 32 and 33 against the bar l2. As the handle 41 is moved downwardly, the spring 50 immediately throws the lower plates into nonbinding relation with the bar l2. and upwardly against the spring plate 66. The parts now are in position again to be engaged by upward manipulation of the handle to lift the housing another increment.

It will be understood that the housing is raised by increments and that each increment is effected by an upward movement of the handle 41. After the housing has been raised sufliciently, and the necessary operations are performed with the vehicle wheel thus raised, release of the housing may be effected by removing the handle 41, inserting it in the slot 42 in the housing wall above the tongue 66, fulcruming it on an edge of the housing at the upper end of the slot 42 and pressing the outer end of the handle downwardly so as to cause the latter to press downwardly against the outer end of the tongue on plate 60. This shifts plates6ll and 6| toward radial positions, thereby releasing their grip on the bar l2 and as the plates begin to lose their grip on the bar H, the weight on the housing tends to moveit downwardly and to cant the plates again to their original position. Thus, by maintaining a slight pressure on the handle, the housing may be allowed to move downwardly in a continuous manner, but as soon as the handle is released from downward pressure, the weight on the housing immediately cants the plates 66 and 6| to effect frictional engagement with the bar.

While in general the operation of the jack is similar to that disclosed in the copending application to which reference has been made, attention is particularly directed to the fact that the two pair of plates of the present invention are provided with jaw elements that have large areas of contact with the bar l2 and thus the frictional engagement between such jaws and the bar is greatly increased. Since canting of the plates of either pair applies pressure to the jaw elements,-

this positive engagement, in conjunction with the plates is required to get the necessary frictional clutch, owing to the larger area of contact, and

thus the parts are subjected to less unit pressure and will not wear as rapidly.

Although only one form of the invention has been described and illustrated in detail, it will be apparent tothose skilled in the art that various modifications may be made without departing from the scope of the appended claims.

What is claimed is:

1. A jack comprising a pair of relatively movable members, one of which is in the form of an elongated bar, a plate having an opening slightly larger than the bar and through which the latter extends, jaw elements serving to form a generally cylindrical resilient sleeve carried by the plate and disposed in said opening for frictional engagement with the bar, and means cooperating with the other member for canting the plate relative to the bar to effect a frictional clutch engagement between the bar and element.

2. A jack comprising a pair of relatively movable members, one of which is in the form of an elongated bar, a plate having an opening slightly larger than the bar and through which the latter extends, jaw elements serving together to form a generally cylindrical resilient sleeve disposed in said opening for frictional engagement with the bar, means for retaining the jaw element in said opening while allowing movement of the element transversely to the bar, and means cooperating with the other member for canting the plate relative to the bar to effect a frictional clutch engagement between the bar and jaw element.

3. A jack comprising a pair of relatively movable members, one of which is in the form of an elongated bar, a plate having an opening slightly larger than the bar and through which the latter extends, a pair of jaw elements serving together to form a generally cylindrical resilient sleeve disposed in said opening for frictional engagement with opposite sides of the bar, means for retaining the jaw elements in said opening while allowing movement of the elements transversely to the bar, and means cooperating with the other member for canting the plate relative to the bar to effect frictional clutch engagement between the barand jaw elements.

4.- A jack comprising a pair of relatively movable members, one of which is in the form of an elongated bar, a pair of plates slidable one on the other and having openings slightly largerthan the bar and through which the latter ex-'- 3 tends, a pair of sheetmetal jaw elements serving to form a generally cylindrical resilient sleeve disposed in said openings at opposite sides of the bar respectively, means for ,retainingthe elements in the openings while allowing movement of the elements transversely to the bar, and means cooperating with the other member for canting the plates relative. to the bar to eflect frictional clutch engagement between the bar and jaw elements. v 5. A jack comprising a pair of relatively movable members, one of which is in the form of an elongated round bar, a plate having an opening slightly larger than the bar and through which the latter extends, a pair of resilient substantially semi-cylindrical sheet metal jaw elements disposed in said opening for frictional engagement respectively with opposite surface portions of the bar, means retaining the elements in the opening while allowing'movement thereof relative to the plate in a direction transversely of the bar, and means cooperating withthe other member for canting the plate relative to the bar to effect frictional clutch engagement between the bar and jaw elements.

. JAMES H. NEEDHAM. 

